1. Field of the Invention
The present invention relates to ground wire connecting structures and, more particularly, to ground wire connecting structures that are mounted to an oil tank.
2. Description of the Related Art
Vehicles having electrical equipment often include ground wire connecting structures. For example, small watercraft automobiles, and boats often include in-vehicle units (e.g., in-vehicle units that include ground wire connecting structures). Japanese Patent Publication No. Hei 2002-301998 discloses an in-vehicle unit for use in automobiles. The in-vehicle unit has an attachment portion made of a conductive material. The in-vehicle unit is attached to a body panel of the vehicle via the attachment portion. A wire harness of an external circuit is connected to the in-vehicle unit. The attachment portion of the in-vehicle unit has a through hole and a projection. The body panel has a threaded hole and a recess that engages the projection of the attachment portion. When the projection engages the recess, a bolt is inserted into the through hole such that the attachment portion is coupled to the body panel. In this manner, the in-vehicle unit is attached to the body panel of the vehicle.
An internal circuit of the in-vehicle unit often has a ground circuit electrically coupled with the attachment portion. The wire harness is typically connected to the in-vehicle unit and includes a ground wire. The ground wire is connected to the body panel via the attachment portion thereby connecting the ground wire to the ground circuit. Thus, the body panel does not need a separate ground wire connecting portion.
Unfortunately these in-vehicle wire connecting structures have a relatively small attachment portion that is fixed to the body panel. A single bolt electrically couples the ground wire with the body panel. Such connections provide poor contact and the in-vehicle unit may not be securely fixed to the body panel.